Safeguard sentry

ABSTRACT

A safeguard sentry for attachment to a radio or television receiving set comprises a receiver independent of the receiving set and responsive to a single predetermined emergency frequency. In one embodiment of the invention, the safeguard sentry is connected between the cut-off switch and the speaker of the receiving set, so that the safeguard sentry is energized when the receiving set is de-energized, and vice versa. In another embodiment of the invention, the safeguard sentry includes a switch which functions in one mode to couple speaker to the safeguard sentry, and in another mode to connect operating power to the receiving set, to couple the speaker of the receiving set to the safeguard sentry, and to activate a visual signaling device. In still another embodiment of the invention, the receipt of an emergency signal by the safeguard sentry activates circuitry which mutes the audio output of the receiving set and simultaneously connects the safeguard sentry to the speaker of the receiving set. Receipt of the emergency signal may also be used to actuate an internal emergency tone signal generator and/or a visual emergency signal apparatus. In all instances in which an audible signal is generated, the safeguard sentry of the present invention produces an output having at least a predetermined volume.

United States Patent 1 Nov. 18, 1975 Baird SAFEGUARD SENTRY [76]Inventor: William C. Baird, 107 W. River St.,

Meridian, Tex. 76665 [22] Filed: July 13, 1973 211 App]. No.: 379,171

Related US. Application Data Primary Examiner-Benedict V. SafourekAttorney, Agent, or Firm-Richards, Harris & Medlock [57] ABSTRACT Asafeguard sentry for attachment to a radio or television receiving setcomprises a receiver independent of the receiving set and responsive toa single predetermined emergency frequency. In one embodiment of theinvention, the safeguard sentry is connected between the cut-off switchand the speaker of the receiving set, so that the safeguard sentry isenergized when the receiving set is de-energized, and vice versa. Inanother embodiment of the invention, the safeguard sentry includes aswitch which functions in one mode to couple speaker to the safeguardsentry, and in another mode to connect operating power to the receivingset, to couple the speaker of the receiving set to the safeguard sentry,and to activate a visual signaling device. In still another embodimentof the invention, the receipt of an emergency signal by the safeguardsentry activates circuitry which mutes the audio output of the receivingset and simultaneously connects the safeguard sentry to the speaker ofthe receiving set. Receipt of the emergency signal may also be used toactuate an internal emergency tone signal generator and- /or a visualemergency signal apparatus. In all instances in which an audible signalis generated, the safeguard sentryof the present invention produces anoutput having at least a predetermined volume.

5 Claims, 6 Drawing Figures 60\ 76 78 SAFEGUARD RECEIVER 1 W80 g: RFCONV IST 2ND DET I VOL AUDIO 82 AMP t AMP l l i TONE GEN. LOCAL AND ORosc 9o SQUELCH FLASHER POWER 96 SUPPLY 66 m, 84 I 62 Q 5 p j RADIOU.S;.- Patent Nov. 18, 1975 Sheet 1 of3 3,921,074

US. Patent Nov. 18,1975 Sheet2Of3 3,921,074

76 SAFEGUARD RECEIVER RF ST 2ND I VOL I 80 1 CONV. OET. AUDIO 82 MP AAMP 94 TONE GEN. LOCAL AND OR 030 90 Q ELCH FLASHER POWER 96 SUPPLY E,Lvfsz \1 k /68 C 7\54 il TV 62 A I OR 5 RADIO US. Patent Nov. 18, 1975Sheet 3 of3 3,921,074

FIG. 4B}

SAFEGUARD SENTRY CROSS REFERENCE TO RELATED APPLICATION This applicationis a continuation-in-part of copending application Ser. No. 17,418,filed Mar. 9, 1970, for SAFEGUARD SENTRY SIGNAL DEVICE.

BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to animproved safeguard sentry, and more particularly to radio receivingapparatus adapted for attachment to a conventional radio or televisionreceiving set to facilitate emergency communications.

The improved safeguard sentry of the present invention is for thepurpose of obtaining immediate emergency communication with the populaceof the United States. The invention is therefore useful in warning oftornadoes, hurricanes, or other capriciousness of elements of nature; inwarning of threat of or actual attack by foreign enemies; to advise ofthreats from public enemies; in deterrence of crime; and especially inthe practicing of Civil Defense exercises.

In practice, the safeguard sentry would be placed on all newlymanufactured radio and television sets as a normal process during theirmanufacture. Apparatus incorporating the same operating principles willbe available for installation on existing radio and televisionreceivers.

The improved safeguard sentry is an electronic device consistingentirely of transistorized and compact circuitry. It is a transistorizedradio receiver responsive to a predetermined emergency frequency, andwill receive only this signal as broadcast or transmitted When theemergency signal is received it is as an electronic tone, beep, squeal,voice, or other signal that is received and amplified, and emitted fromthe speaker of the radio or television set to which it is applied, saidsignal having at least a predetermined volume.

In one embodiment the safeguard sentry is power on at all times when theradio or television is switched to the off position, thus requiring noconscious act to place it in operation. When the power switch of theradio or television is turned to off position, the safeguard sentry isalert and at work, thus assuring an available audience 24 hours a day.When the power switch of the radio or television is turned to onposition, this cuts off the power to the safeguard sentry.

As an example, the proper authority may broadcast theemergencysignalabove-described, and the safeguard sentry immediately begins toemit the signal, ;which may be a squeal. The owner of the radio ortelevision set then turns the set on to receive the broadcastinstructions from the authority, and through this act simultaneouslyturns off the squeal or signal. If no one is in ear shot of the signalit simply continues until the emergency signal ceases, and stops,neither disturbing nor advising anyone, and damaging or harming nothing.

The service which may be rendered by the safeguard sentry of theinvention should be appreciated and in demand in the event of any formof enemy attack, such the approach or imminence of assault by plane ormissile, to serve in keeping an evenly informed public, to rally forces,and above all to help forestall panic, one of the most grave threats tobe faced by at home America".

In another embodiment the safeguard sentry includes a switch having twooperating modes. In one mode the switch connects the safeguard sentry toa speaker which may comprise an internal speaker. In the other operatingmode, the switch of the safeguard sentry connects operating power to thereceiving set. In this mode the switch also connects the output of thesafeguard sentry to the speaker of the receiving set and enables avisual signaling apparatus. The visual signaling apparatus is actuatedin response to the receipt of an emergency signal by thesafeguard'sentry, and functions to warn both deaf persons and persons ina high background noise environment. Regardless of the operating mode,the safeguard sentry includes a volume control which prevents theaudible output of the apparatus from being reduced below a predeterminedlevel.

In still another embodiment the safeguard sentry includes circuitryresponsive to the receipt of an emergency signal by the safeguard sentryto mute the speaker of the receiving set. This embodiment may furtherinclude apparatus for generating an internal tone signal and/or a visualoutput in response to receipt of the emergency signal by the safeguardsentry. Regardless of whether the emergency signal is reproduced or aninternal tone signal is generated, the audible portion of the warningsignal provided by the third embodiment of the invention has at least apredetermined volume.

DESCRIPTION OF THE DRAWINGS A more complete understanding of theinvention may be had by referring to the following Detailed Descriptionwhen taken in conjunction with the accompanying Drawings, wherein:

FIG. 1 is a somewhat diagrammatic illustration of a safeguard sentryincorporating a first embodiment of the invention;

FIG. 2 is a front perspective view of a safeguard sentry incorporating asecond embodiment of the invention;

FIG. 3 is a rear perspective view of the embodiment illustrated in FIG.2;

FIGS. 4a and 4b are illustrations of a switch utilized in the embodimentof the invention shown inFIGS. 2 and 3; and

FIG. 5 is a schematic illustration of a safeguard sentry incorporating athird embodiment of the invention.

DETAILED DESCRIPTION Referring now to the Drawings, and particularly toFIG. 1 thereof, there is shown a safeguard sentry 10 incorporating afirst embodiment of the invention. The safeguard 'sentry 10 comprises aradio receiver 12 responsive to a predetermined emergency frequency toemit a tone, beep, squeal or other signal and is utilized in conjunctionwith a conventional radio or television receiving set 14 having theusual cut-off switch l6,and speaker 18. The safeguard sentry 10comprising the first embodiment of the invention may be constructedsimilarly to radio paging devices presently in commercial use, andpreferably comprises a transistorized radio receiver tuned to apredetermined frequency and characterized by extremely low currentrequirements. In accordance with the first embodiment, the safeguardsentry operates from the same power source as the receiving set whichmay comprise volt, 60 hz line current, for example.

In accordance with the first embodiment of the invention, the safeguardsentry is operatively connected to the cut-off switch 16 and the speaker18 of the receiving set 14, it being understood that these twocomponents are common both to the receiving set and to the safeguardsentry. The cut-off switch is operable as a selector or transfer switch,whereby either the re ceiving set 14 or the receiver 12 is continuouslyin operation depending on the position of the switch. Stated anotherway, the safeguard sentry is turned on at all times when the receivingset is turned off, and the safeguard sentry is turned off, at all timeswhen the receiving set is turned on. It will thus be understood that inaccordance with the first embodiment of the invention the safeguardsentry operates out of phase with the radio or television receiving set.By this means whenever the receiving set is off the safeguard sentry isavailable to receive an emergency signal and to generate an audiblereproduction thereof. This in turn advises persons in the vicinity ofthe receiving set to turn the receiving set on, whereby emergencybroadcast information is received by means of conventional broadcastcommunications. The safeguard sentry is turned of whenever the receivingset is on to prevent interference from the emergency signal with theemergency broadcast information, and to conserve power.

An important feature of the safeguard sentry 10 comprises the fact thatwhereas the receiver 12 may be provided with a suitable volume control,such control does not permit the output voltage produced by the receiver12 in response to receipt of a signal at the emergency frequency to bereduced below a predetermined magnitude. This assures that the speaker18 of the receiving set 14 will be actuated to produce an audiblewarning having at least a predetermined volume.

Referring now to FIGS. 2 and 3, a safeguard sentry 20 comprising asecond embodiment of the invention is shown. The safeguard sentry 20includes a cabinet 22 which is preferably formed from metal or one ofthe tough plastic materials so as to prevent access to the componentparts of the safeguard sentry 20 by unauthorized persons. The cabinet 22may be provided with conventional brackets 24 and/or conventionalattachment holes 26, whereby the safeguard sentry 20 is secured to thecabinet of a radio or television receiving set, or in any otherconvenient location.

Referring particularly to FIG. 3, operating power for the safeguardsentry is supplied by means of a power cord 28 and a plug 30 whichengages a conventional convenience outlet 32. The safeguard sentry 20 inturn supplies operating power to the receiving set by means of a cord34. The cord 34 is connected to the cabinet 22 of the safeguard sentryby means of a special connector 36 which prevents disengagement of thecord 34 from the cabinet 22. The safeguard sentry 20 further includesoutput jacks 38 for connection to the speaker of the receiving set andoutput jacks 40 for connection to the visual signaling apparatus.

Referring again to FIG. 2, the safeguard sentry 20 may be provided withan internal speaker 42. Regardless of whether the speaker 42 is used, avolume control 44 is provided in the safeguard sentry 20. The volumecontrol 44 permits any desired increase in volume up to a predeterminedmaximum, but prevents reduction in volume below a predetermined minimum,thereby preventing disabling of the safeguard sentry 20 by means of thevolume control 44. The safeguard sentry 20 further includes a controlswitch 46.

The control switch 46 of the safeguard sentry 20 has two operating modeswhich are illustrated in FIGS. 4a and 4b, respectively. In one operatingmode the switch 46 connects the output of the safeguard sentry 20 to theinternal speaker 42. In this operating mode, an emergency signalreceived by the safeguard sentry 20 is reproduced directly thereby.

In the other operating mode, the switch 46 connects operating power fromthe safeguard sentry 20 to a radio or television receiving set 48. Inthis mode the switch 46 also connects the output of the safeguard sentry20 to a speaker 50 mounted within the receiving set 48 and to a visualsignaling apparatus 52. The visual signaling apparatus 52 preferablycomprises a light emitting diode (LED) or similar electronic componenthaving an extended operating life, and functions to provide an emergencywarning signal to deaf persons and- /or persons who may be situated in ahigh background noise environment.

It will thus be understood that the safeguard sentry 20 differs from thesafeguard sentry 10 in that the safeguard sentry 20 is continuously inthe on condition. When the control switch 46 of the safeguard sentry 20is in one operating mode, the safeguard sentry 20 reproduces anemergency signal through the internal speaker 42. When the switch 46 isin the other operating mode, operating power is directed to theassociated receiving set and the emergency signal is generated throughthe speaker of the receiving set. The safeguard sentry 20 is furtheradapted to provide a visual emergency signal.

A safeguard sentry 60 comprising a third embodiment of the invention isillustrated in FIG. 5. Operating power for the safeguard sentry 60 isreceived from a conventional convenience outlet through a plug 62 and acord 64. The cord 64 extends to a conventional power supply circuit 66which functions to supply operating power for the remaining componentsof the apparatus.

Operating power is also supplied from the safeguard sentry 60 to a radioor television receiving set 68. The receiving set 68 is connected to thesafeguard sentry 60 by means of a plug 70 and a cord 72. The plug 70 issecured by a threaded fitting 74 which is so constructed that it cannotbe disassembled without destroying the plug 70. By this meansdisengagement of the electrical connection from the receiving set 68 tothe safeguard sentry 60 by unauthorized persons is prevented.

The safeguard sentry 60 includes an antenna 76 and a single conversionheterodyne circuit 78 for receiving an emergency signal. The output ofthe circuit 78 actuates an audio amplifier circuit 80 and a tonegenerator and/or flasher actuator circuit 82, thereby assuring operationof the safeguard sentry 60 in response to receipt of the emergencysignal. The radio or television receiving set 68 includes conventionalcircuitry 86 for generating an audible output through a speaker 88. Thiscircuitry is normally connected to the speaker 88. through normallyclosed contact pairs 90 and 92 located within the safeguard sentry 60.Upon receipt of an emergency signal, the safeguard sentry 60, by meansof a squelch circuit 84, energizes a relay 94 which functions to openthe contact pairs 90 and 92 and to close two normally open contact pairs96 and 98. By this means the audible output'from the receiving set 68 isimmediately muted,

and the speaker 88 of the receiving set is coupled to the audioamplifier circuitry 80 of the safeguard sentry. The emergency signalreceived by the safeguard sentry 60 is thereupon reproduced through thespeaker 88 of the receiving set 68.

It will be understood that in addition to reproducing the emergencysignal through the speaker 88, the receipt of the emergency signalby thesafeguard 60 may be utilized to actuate the tone generator and/orflasher actuator circuit 82 to produce an internally generated audiblealarm signal. The circuit 82 may also actuate apparatus 100 forproducing a visual emergency signal. As has been explained previously,the apparatus 100 preferably comprises a light emitting diode-(LED) orsimilar electronic component designed to provide an extended servicelife.

The use of the safeguard sentry 60 produces a visual emergency signalwhich is primarily for the purpose of emergency communications with deafpersons and/or persons situated in a high background noise environ ment.To this end, the visual signal generating apparatus 100 may be locatedat a convenient point on the receiving set 68, or at any other locationwhereupon it will be readily visible to persons in the vicinity of thesafeguard sentry 60. It is assumed that upon receiving the emergencysignal by means of the apparatus 100, such persons would turn to thereceiving set 68 or other apparatus to ascertain the precise nature ofthe emergency condition.

The safeguard sentry 60 also produces an audible emergency signal,either by reproducing the received emergency signal through the speaker88 of the receiving set 68, or by means of the circuit 82, or both.Regardless of the mode used to produce the audible sig nal, thesafeguard sentry 60 is preferably so designed that the volume of theaudible signal cannot be reduced below a predetermined level. in thecase of the circuit 82, a predetermined fixed volume can be used, ifdesired. In the case of the audio amplifier circuit 80, it is soconstructed that the voltage output produced thereby has at least apredetermined magnitude, thereby assuring actuation of the speaker ofthe receiving set to produce an audible warning signal having at least apredetermined volume.

Those skilled in the art will appreciate the fact that whereas threedistinct embodiments of the safeguard sentry have been illustrated inthe accompanying Drawings and described herein, the three embodimentsincorporate various features in common, all of which are very importantto the present invention. Perhaps most importantly, all of theembodiments contemplate the use of transistorized receiver circuitryresponsive to a single, predetermined emergency frequency and entirelyindependent of the circuitry of the associated receiving set. This isimportant because it facilitates both optimization of the design of theemergency frequency receiving circuitry and optimization of the designof the circuitry of the broadcast receiving set. Moreover, the use ofentirely separate circuitry for the receiving set and the emergencyfrequency receiver does not increase the overall costs involved in theuse of the invention due to the fact that by means of modern MOS andsimilar technologies, a single, uniform design emer- It will be furtherappreciated that various modifications can be made to the variousspecific embodiments of the safeguard sentry which have been illustratedin the Drawings. For example, the safeguard sentry illustratedin FIG. 5is readily adapted for use in automobiles or other vehicles.v In suchinstances the-safeguard sentry-is modified for actuation by theelectrical system .of the vehicle,-and for use in conjunction with thespeaker of theradio receiverof the vehicle. Moreover, the safeguardsentry is connected in series with the ignition switch of thevehicle sothat the safeguard sentry is on whenever-the vehicle is in use, and isoff whe'neverthe vehicle isout of service. By this means the-safeguardsentry is constantly available to provide .emergency communicationswhenever an operator ,is

situated in or-around the. vehicle, but does not drain power from thebattery of the vehicle when the vehicle is out of service. Similarmodifications can be made in the safeguard sentry to permit utilizationof the invention in conjunction with portable radios, and the like.

From the foregoing itwill be understood that the present inventionrelates to a safeguard sentry adapted to provide emergencycommunications with the citi zenry of the United States. The use of theinvention is highly advantageous in that the safeguard sentry comprisesa transistorized radio receiver responsive to a particular emergencyfrequency and having very low power requirements. It will thus beunderstood that the safeguard sentry comprises a highly reliable,economical and thoroughly dependable emergency communication system.Moreover, the safeguard sentry of the present invention is adapted notonly for incorporation into newly manufactured radio and televisionreceiving sets, but also as an attachment to existing receiving sets.

Although preferred embodiments of the invention have been illustrated inthe accompanying Drawings and described in the foregoing DetailedDescription, it will be understood that the invention is not limited tothe embodiments disclosed, but is capable of numerous rearrangements,modifications, and substitutions of parts and elements without departingfrom the spirit of the invention.

What is claimed is:

l. Safeguard sentry circuitry which is continually energized to receivetransmitted emergency information, comprising:

a tunable receiving set having a speaker connected thereto for producingan audible output, said tunable receiving set being tunable to anydesired carrier frequency within its tuning range for providing ordinaryprogramming audio output at said speaker;

an emergency signal receiver means independent of said tunable receivingset and being pretuned to a single predetermined emergency carrierfrequency, said emergency signal receiver having radiofrequency andaudio-frequency stages entirely distinct from those of said tunablereceiving set for converting a received modulated emergency transmissionat said predetermined carrier frequency into a correspondingaudio-frequency output; and

means for coupling said speaker of said tunable receiving set to theoutput of said emergency signal receiver means, said coupling meansbeing operative to couple said speaker to the output of said emergencysignal receiver means during the reception of any such audio frequencyoutput'irrespec tive of the frequency of the modulation of suchemergency transmission signal and the corresponding frequency of suchaudio output of said emergency signal receiver.

2. The safeguard sentry circuitry of claim 1, further comprising manualswitching means for alternatively energizing said emergency signalreceiver means and said tunable receiving set such that said emergencysignal receiver is energized whenever said tunable receiving set isdeenergized and vice versa.

3. The safeguard sentry circuitry of claim 1, further comprising manualswitching means associated with said emergency signal receiver means forselectively energizing said tunable set while simultaneouslycontinuously providing energy to said emergency signal receiver suchthat said emergency signal receiver is energized independent of saidtunable receiving set.

4. The safeguard sentry circuitry of claim 1, further comprising meansfor automatically muting the audio output of said tunable receiving setupon the reception of a modualted emergency transmission by saidemergency signal receiver.

5. Safeguard sentry circuitry for producing an audible alarm signal uponreceipt of a predetermined emergency frequency signal, comprising:

a tunable receiving set having a speaker connected thereto for producingan audible output, said tunable receiving set being tunable to anydesired carrier frequency within its tuning range for providing ordinaryprogramming audio output at said speaker;

an emergency signal receiver means independent of said receiving set andbeing pretuned to a single predetermined emergency carrier frequency,said emergency signal receiver having radio-frequency andaudio-frequency stages entirely distinct from those of said tunablereceiving set for converting a received modulated emergency transmissionat said predetermined carrier frequency into a correspondingaudio-frequency output of at least a predetermined amplitude; and

means for coupling said speaker of said tunable receiving set to theoutput of said emergency signal receiver means to produce an audiblealarm signal of at least a predetermined volume, said coupling meansbeing operative to couple said speaker to the output of said emergencysignal receiver means during the reception of any such audio frequencyoutput irrespective of the frequency of modulation of such emergencytransmission signal and the corresponding frequency of such audio outputof said emergency signal receiver.

1. Safeguard sentry circuitry which is continually energized to receivetransmitted emergency information, comprising: a tunable receiving sethaving a speaker connected thereto for producing an audible output, saidtunable receiving set being tunable to any desired carrier frequencywithin its tuning range for providing ordinary programming audio outputat said speaker; an emergency signal receiver means independent of saidtunable receiving set and being pretuned to a single predeterminedemergency carrier frequency, said emergency signal receiver havingradio-frequency and audio-frequency stages entirely distinct from thoseof said tunable receiving set for converting a received modulatedemergency transmission at said predetermined carrier frequency into acorresponding audiofrequency output; and means for coupling said speakerof said tunable receiving set to the output of said emergency signalreceiver means, said coupling means being operative to couple saidspeaker to the output of said emergency signal receiver means during thereception of any such audio frequency output irrespective of thefrequency of the modulation of such emergency transmission signal andthe corresponding frequency of such audio output of said emergencysignal receiver.
 2. The safeguard sentry circuitry of claim 1, furthercomprising manual switching means for alternatively energizing saidemergency signal receiver means and said tunable receiving set such thatsaid emergency signal receiver is energized whenever said tunablereceiving set is deenergized and vice versa.
 3. The safeguard sentrycircuitry of claim 1, further comprising manual switching meansassociated with said emergency signal receiver means for selectivelyenergizing said tunable set while simultaneously continuously providingenergy to said emergency signal receiver such that said emergency signalreceiver is energized independent of said tunable receiving set.
 4. Thesafeguard sentry circuitry of claim 1, further comprising means forautomatically muting the audio output of said tunable receiving set uponthe reception of a modualted emergency transmission by said emergencysignal receiver.
 5. Safeguard sentry circuitry for producing an audiblealarm signal upon receipt of a predetermined emergency frequency signal,comprising: a tunable receiving set having a speaker connected theretofor producing an audible output, said tunable receiving set beingtunable to any desired carrier frequency within its tuning range forproviding ordinary programming audio output at said speaker; anemergency signal receiver means independent of said receiving set andbeing pretuned to a single predetermined emergency carrier frequency,said emergency signal receiver havIng radio-frequency andaudio-frequency stages entirely distinct from those of said tunablereceiving set for converting a received modulated emergency transmissionat said predetermined carrier frequency into a correspondingaudio-frequency output of at least a predetermined amplitude; and meansfor coupling said speaker of said tunable receiving set to the output ofsaid emergency signal receiver means to produce an audible alarm signalof at least a predetermined volume, said coupling means being operativeto couple said speaker to the output of said emergency signal receivermeans during the reception of any such audio frequency outputirrespective of the frequency of modulation of such emergencytransmission signal and the corresponding frequency of such audio outputof said emergency signal receiver.